Reduced capacity carrier, transport, load port, buffer system

ABSTRACT

A semiconductor workpiece processing system having at least one processing apparatus for processing workpieces, a primary transport system, a secondary transport system and one or more interfaces between first transport system and second transport system. The primary and secondary transport systems each have one or more sections of substantially constant velocity and in queue sections communicating with the constant velocity sections.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of U.S. Ser. No. 11/556,584, filedNov. 3, 2006 which claims the benefit of U.S. Provisional ApplicationNo. 60/733,813 filed Nov. 7, 2005 which is incorporated by referenceherein in its entirety.

FIELD

The exemplary embodiments described herein are related to substrateprocessing systems and particularly to substrate transport systems,transport carriers, transport to processing tool interfaces andarrangements.

EARLIER RELATED EMBODIMENTS

The prime forces on the fabrication of electronic devices are theconsumer desire for more capable, and smaller electronic devices atlower costs. The primal forces translate to an impetus on manufacturersfor further miniaturization and improvements in fabrication efficiency.Manufacturers, thus seek gains wherever possible. In the case ofsemiconductor devices, the conventional fabrication facility or FAB hasat its heart (or base organizational structure) the discrete processingtool, for example a cluster tool, for performing one or more processesto semiconductor substrates. Conventional FABs are hence organizedaround the processing tool, that may be arranged in desiredconfigurations to transform the semiconductor substrates into desiredelectronic devices. For example, the processing tool may be arrayed inthe conventional FAB in processing bays. As may be realized, betweentools, substrates may be held in carriers, such as SMF's, FOUP's, sothat between tools substrates in process may remain in substantiallysimilar cleanliness conditions as within the tools. Communicationbetween tools may be provided by handling systems (such as automatedmaterial handling systems, AMHS) capable of transporting substratecarriers to the desired processing tools in the FAB. Interface betweenthe handling system and processing tool may be considered for examplepurposes as having generally two parts, interface between handlingsystem and tool to load/unload carriers to the loading stations of theprocessing tool, and interface of the carriers (i.e. (individually or ingroups) to the tool to allow loading and unloading or substrates betweencarrier and tool. There are numerous conventional interface systemsknown that interface the processing tools to carriers and to materialhandling systems. Many of the conventional interface systems suffer fromcomplexity resulting in one or more of the process tool interface, thecarrier interface or the material handling system interface havingundesired features that increase costs, or otherwise introduceinefficiencies in the loading and unloading of substrates in processingtools. The exemplary embodiments described in greater detail belowovercome the problems of conventional systems.

SUMMARY OF THE EXEMPLARY EMBODIMENT(S)

In accordance with an exemplary embodiment of a semiconductor workpieceprocessing system is provided. The system has at least one processingapparatus for processing workpieces, a primary transport system, asecondary transport system and one or more interfaces between firsttransport system and second transport system. The primary and secondarytransport systems each have one or more sections of substantiallyconstant velocity and in queue sections communicating with the constantvelocity sections.

BRIEF DESCRIPTION OF DRAWINGS

The foregoing aspects and other features of the present invention areexplained in the following description, taken in connection with theaccompanying drawings, wherein:

FIG. 1 is a schematic elevation view of a workpiece carrierincorporating features in accordance with an exemplary embodiment, and aworkpiece or substrate S positioned on the carrier; and FIGS. 1A-1B arerespectively schematic partial plan and elevation views of a workpiecesupport of the carrier in accordance with another exemplary embodiment,

FIG. 2A is a schematic cross-sectional elevation view of the carrier inFIG. 1 and a tool port interface in accordance with another exemplaryembodiment;

FIG. 2B is another schematic cross-section elevation of a tool portinterface and carrier in accordance with another exemplary embodiment;

FIGS. 3A-3C are schematic cross-section elevation views respectivelyillustrating a tool port interface and carrier, in accordance withanother exemplary embodiment, in three different positions;

FIG. 4 is a schematic elevation view of a carrier and tool interface inaccordance with yet another exemplary embodiment, and FIGS. 4A-4C arerespectively enlarged cross-sectional views of a portion of theinterface between carrier and tool each illustrating the interfaceconfiguration in accordance with different exemplary embodiments,

FIGS. 5A-5C are schematic partial elevation views of a carrier and toolinterface in accordance with yet another exemplary embodiment, showingthe carrier and tool interface in three respective positions.

FIG. 6A-6B are respectively schematic elevation views of workpiececarriers in accordance with other different exemplary embodiments;

FIGS. 7A-7B are schematic elevation views of a workpiece carrier, inaccordance with another exemplary embodiment, respectively showing thecarrier in different positions;

FIG. 8 is another schematic elevation view of tool interface and carrierin accordance with another exemplary embodiment,

FIG. 9 is another schematic elevation view of tool interface and carrierin accordance with another exemplary embodiment;

FIG. 10 is another schematic elevation view of tool interface andcarrier in accordance with another exemplary embodiment, and FIG. 10A isa schematic partial elevation of a process tool and carrier interfacedtherewith in accordance with another exemplary embodiment;

FIG. 11 is a schematic elevation view of a process tool section andcarrier interface therewith in accordance with another exemplaryembodiment;

FIGS. 12A-12B are schematic bottom views of the carrier (workpiecetransfer) opening and carrier door of the carrier in FIG. 11;

FIGS. 13A-13B are schematic top plan views of the interface and a toolto carrier door interface of the tool section in FIG. 11;

FIG. 14 is a schematic elevation of a process tool and carrierinterfaced therewith in accordance with still another exemplaryembodiment;

FIG. 15 is a schematic elevation view of a tool interface and carrier inaccordance with yet another exemplary embodiment;

FIGS. 16A-16B are schematic elevation views of a tool interface andcarrier respectively shown on two different positions in accordance withanother exemplary embodiment;

FIG. 17 is a schematic side view of a carrier, and FIGS. 17A-17C areother schematic elevation views of the carrier and a tool interface anda plan view of the tool interface in accordance with another exemplaryembodiment;

FIGS. 18-19 are schematic elevation views of a tool interface andcarrier in accordance with another exemplary embodiment;

FIG. 20 is a schematic plan view of a transport system in accordancewith another exemplary embodiment;

FIGS. 20A-20B are schematic partial plan views of portions of thetransport system track in FIG. 10; and FIGS. 20C-20D are schematicbottom views of a different payloads of the transport system inaccordance with other exemplary embodiments;

FIG. 21 is a schematic partial plan view of another portion of thetransport system in accordance with another exemplary embodiment;

FIGS. 22-24 are other schematic partial plan views of portions of thetransport system in accordance with other exemplary embodiments;

FIGS. 25A-25B respectively show different elevation views of a transportsystem and processing tool in accordance with another exemplaryembodiment;

FIGS. 26A-26B respectively show different schematic elevation views of atransfer interface system for transferring carriers between transportsystem and tool in accordance with another exemplary embodiment;

FIG. 27 is a schematic partial elevation view of a transport system inaccordance with another exemplary embodiment and FIGS. 27A-27B are otherschematic partial elevations of the transport system in differentpositions;

FIG. 28 is another schematic elevation view of a transport system inaccordance with another exemplary embodiment;

FIGS. 29A-29B are schematic plan views of transport systems inaccordance with another exemplary embodiment;

FIG. 29C is a schematic plan view of a transport system and processingtools in accordance with another exemplary embodiment;

FIG. 30 is a schematic partial elevation of the transport system andprocessing tools in FIG. 29C;

FIG. 31 is another schematic partial elevation of the transport system;

FIG. 32 is another schematic partial elevation of the transport systemin accordance with another exemplary embodiment;

FIGS. 33-34 are respectively schematic plan and elevation views ofanother transport system in accordance with other exemplary embodiments;and

FIG. 35 is yet another schematic plan view of a transport system inaccordance with another exemplary embodiment.

DESCRIPTION OF THE EMBODIMENT(S)

Still referring to FIG. 1, the workpiece carrier 200 defines a chamber202 in which workpieces S may be carried in an environment capable ofbeing isolated from the atmosphere exterior to the chamber. The shape ofthe carrier 200 shown in FIG. 1 is merely exemplary, and in alternateembodiments the carrier may have any other desired shape. The carrier200 may be capable of accommodating a cassette 210 inside the chamberfor supporting the workpieces S within the carrier as shown. Thecassette 210 generally has elongated supports 210S (in the embodimenttwo are shown for example) with workpiece support shelves 210Vdistributed thereon to provide a row or stack of supports, or shelves onwhich one or more workpieces may be individually supported as shown. Thecassette may be mounted or otherwise attached to the carrier structure,and will be described in greater detail below. In alternate embodiments,the carrier may not have a cassette, and the workpiece supports may beintegral or formed as a unitary construction with the carrier structure.The workpieces are shown as flat/substrate elements, such as 350 mm, 300mm, 200 mm or any desired size and shape semiconductor wafers, orreticles/masks or flat panels for displays or any other suitable items.The carrier may be a reduced or small lot size carrier, relative toconventional 13 or 25 wafer carriers. The carrier may be configured tocarry a small lot with as few as one workpiece, or may be configured tocarry small lots of less than ten workpieces. Suitable examples ofreduced capacity carriers, similar to carrier 200, are described andshown in U.S. patent application Ser. No. 11/207,231, filed Aug. 19,2005, titled “Reduced Capacity Carrier and Method of Use”, incorporatedby reference herein in its entirety. Suitable examples of interfacesbetween the carrier, similar to carrier 200, and processing tools (e.g.semiconductor fabrication tools, stockers, sorters, etc.), and transportsystems are described and shown in U.S. patent application Ser. No.11/210,918, filed Aug. 23, 2005, titled “Elevator Bases Tool Loading andBuffering System”; and Ser. No. 11/211,236, filed Aug. 24, 2005, titled“Transportation System”, both of which are incorporated by referenceherein in their entirety. Another suitable example of a carrier, withfeatures similar to carrier 200, is described and shown in U.S.application Ser. No. 10/697,528, filed Oct. 30, 2003, titled “AutomatedMaterial Handling System” and also incorporated by reference herein inits entirety. As may be realized, a reduced size carrier, similar tocarrier 200, allows reduction of work in process in the FAB as theworkpieces forming smaller lots may be immediately (upon completion ofprocessing at a given workstation) transported to following workstationsin the FAB without waiting for completion of processing of otherworkpieces as would occur in larger lots. Though the features of theexemplary embodiments are described and shown with specific reference tosmall capacity carriers, the features of the exemplary embodiments applyequally to any other suitable carrier, such as carriers capable ofhousing 13, or 25, or any other desired number of workpieces therein.

Referring still to FIG. 1, in the exemplary embodiment, carrier 200 maybe shaped to hold the workpieces in a vertical (i.e. Z axis) stack.Carrier 200 may be a bottom or top opening or bottom and top openingcarrier. In the exemplary embodiment shown, top and bottom are disposedalong the vertical or Z axis, though in alternate embodiments top andbottom may be oriented along any other axis. Top and bottom openings,which will be described in greater detail below, means that theopening(s) 204 of the carrier (though which workpieces S moved in andout of the chamber 202, defined by the carrier) are substantiallyaligned with the planar surface of the workpieces held in the carrier(in this embodiment substantially orthogonal to Z axis). Carrier 200 aswill also be seen below, generally has a casing 212 with a base and aclosable or removable door. When closed, the door may be locked andsealed to the base. The seal between door and base may allow the chamber202 to be isolated from the exterior atmosphere. The isolated chamber202 may hold any desired isolated atmosphere, such as clean air, aninert gas, or may be capable of holding a vacuum. The door may be openedto allow workpieces to be loaded/unloaded from the carrier. In theexemplary embodiment, door means a removable or removed portion when thecarrier is opened to access the workpieces/workpiece support shelvestherein. In the exemplary embodiment shown in FIG. 1, casing 200generally has a generally recessed or hollow portion (referred tohereafter as the shell) 214 capable of receiving the workpieces therein,and a wall (cap/cover, etc.) 216. As will be described below, eitherwall 216, or shell 214 may operate as the carrier door. The wall andshell are mated to close the carrier, and are separated to open thecarrier. In the exemplary embodiment, the shell and wall may be metal,such as an aluminum alloy, or stainless steel made by any suitableprocess. The wall or shell or both may be one piece members (unitaryconstruction). In alternate embodiments, the carrier casing may be madeof any other suitable materials including suitable non metallicmaterials. Cassette 210 may be mounted to the wall 216, though inalternate embodiments the cassette may be mounted to the shell. Mountingof the cassette to either the shell or door may be selected tofacilitate ease of removal of the cassette, or substrates therein fromthe carrier when the door is opened. Though in the embodiment shown wall216 is located on top of the shell, in alternate embodiments the carriercasing may have a configuration with the shell on top and wall on thebottom. In still other embodiments, the shell may have a removable wallboth on top and bottom (i.e. carrier with top and bottom openings). Inother alternate embodiments, the removable wall may be located on alateral side of the carrier. In the exemplary embodiment, the door maybe a passive component (for example, substantially without moving partsor components to effect closing and opening between door and carrier andbetween door and tool interface as will be described further below).

Referring now to FIG. 2A, carrier 200 is shown positioned at a tool portinterface 2010 of a suitable processing tool. The processing tool may beof any desired type, for example a sorter, stocker, or a tool capable ofone or more processes, such as material deposition, lithography,masking, etching, polishing, metrology, or a tool with one or moreprocess modules or chambers such as a load lock. The processing tool mayhave a controlled atmosphere, at least in part, and the tool interface2010 allows loading/unloading of workpieces between tool and carrier 200without compromising the controlled atmosphere in tool or carrier 200.In the exemplary embodiment, the port interface 2010 may generally havea port or opening 2012, through which substrates may be loaded into theprocessing tool, and a door, cover or removable portion 2014 closing theport. In alternate embodiments the removable portion may block theopening in part. In FIG. 2A, the port door 2014 is shown in closed andopen positions for example purposes. In the embodiment shown in FIG. 2A,the carrier 200 may be bottom loaded (i.e. moved in Z direction) tointerface with the tool port 2012 as will be described below. FIG. 2Ashows top wall 216 operating as the door for carrier 200. For example,wall 216 may be connected to the port door 2014 and removed in unisonwith removal of the port door, for example into the tool, to open thetool port interface. Removal of the wall 216, causes removal of thecassette (mounted thereon) and workpieces thereon from the carrier (foraccess by a workpiece transport/robot). Referring again to FIG. 1, theconfiguration of cassette 210 with opposing supports 210S, provideaccess areas 210A, 210B on more than one side of the cassette (in theexemplary embodiment two sides) which workpiece robot(s) (see also FIG.2A) may load/unload workpieces onto the cassette shelves. In alternateembodiments the carrier may have any desired number of workpiece accessareas. The access areas may be arranged symmetrically around theperimeter of the carrier, or may be disposed in an asymmetricconfiguration. In the exemplary embodiment shown in FIG. 2A, the toolmay have more than one workpiece handling robot 2016A, 2016B to accessfor example the workpieces V in the more than one access areas 210A,210B. In alternate embodiments, the tool may have more or fewerworkpiece transport robots. Multiside robot access to the cassette mayallow workpiece hand off between robots at the cassette. Also,multisided robot access to workpieces delimits the orientation of thecarrier when transported or interfaced to tool port. Accordingly, thecarrier 200 may be mated to the tool interface in more than oneorientation relative to the tool interface. The carrier is closed byreturning the port door to its closed position which returns the carrierwall 216 to mate with shell 214.

Referring to FIG. 2B, there is shown the interface of carrier 200 with atool port interface 2010′ in accordance with another exemplaryembodiment. In this embodiment, the shell 214 of the carrier may operateas the door. In the embodiment shown the tool port door 2014′ may have ashape generally conformal to the carrier shell, to surround and sealaround the shell in order to prevent exposure inside the tool interiorto contamination on the outside of the shell. In the exemplaryembodiment, the carrier 200 may be top loaded, (i.e. moved down along(−) Z direction) such as when the carrier is being lowered from anoverhead transport system. To open the carrier 200, the port door ismoved down (direction (−)Z), for example into the tool interior,simultaneously removing the shell 214 from the carrier. This may bereferred to as bottom opening the carrier, in that the carrier door here(i.e. shell 214) is located on the bottom and opens the carrier bydownward movement. The opening of the carrier, exposes the workpieces inthe cassette, which remain with wall 216. In this embodiment, the robot(similar to robot(s) 2016A, 2016B in FIG. 2A) may be provided withdegree of freedom in Z axis to access the vertically spaced cassetteshelves or workpieces therein. The robot may have a mapper (not shown)thereon. In alternate embodiments, the shell 216 may have an integralmapper, such as a through beam mapper allowing mapping of the cassetteon removal of the shell. FIGS. 2A-2B illustrate that carrier 200 may beboth top and bottom opening. In other alternate embodiments, the shelland wall orientation may be reversed (shell on top of wall) and thecarrier may be top opening in a similar but mirror image to FIG. 2B(i.e. lifting shell up) and bottom opening in a manner similar butopposite to FIG. 2A (i.e. lowering wall down).

Referring again to FIG. 1, as noted before the wall 216 and shell 214may be passive structures, without movable elements, such as locks,which have the potential for generating contamination by actuationwithin the tool or container clean space. For example, the wall andshell may be magnetically locked to each other. Magnetic locks forexample, may have permanent or electromagnetic elements 226, 228 or acombination thereof may be positioned as desired in wall 216 and shell214 to lock and release wall and shell. The magnetic locks may forexample have a reversible magnetic element that is switched (i.e. toopen or close) by passing a charge through the reversible element. Forexample, the wall 216 may include magnetic elements 228 (for exampleferrous material) and the shell 214 may have a magnetic switch elements226 actuated to lock and unlock the wall and shell. In the exemplaryembodiment shown in FIGS. 2A, 2B, the magnetic elements in the wall, andthe operable magnets in the shell may be configured to allow cooperationwith magnetic locks 2028′, 2026′ in the port door interface 2010, 2010′so that locking the carrier door (either wall or shell, see FIGS. 2A-2B)to the port door causes unlocking of the carrier door from the rest ofthe carrier. In alternate embodiments, the magnetic locks between walland shell may have any other desired configuration. In the exemplaryembodiment shown in FIG. 23 the carrier may include mechanical couplingelements 230, such as actuated pins, piezo coupling devices or shapememory devices to engage mating coupling features 2030 on the portinterface and interlock the carrier to the port interface. In theexemplary embodiment, the devices are shown located in the wall portion,but in alternate embodiments the devices may be locked in the shell. Asmay be realized from FIG. 24, the actuable devices are enclosed in thesealed interface between the removable wall portion and port doortrapping potential particulates, that may arise by operation of thedevices therein. The passive carrier and carrier door provide a clean,washable carrier that is vacuum compatible.

As noted before, the carrier door and base (i.e. wall 216 and shell 224)may be sealed to isolate the carrier chamber 202. Also, when the carrieris interfaced with the port of a tool, (for example a load port module),the carrier door and base may each have sealing interfaces forrespectively sealing the carrier door (i.e. wall 216 or shell 214 inFIG. 1) to the port door and the carrier base to the port. Further, theport door may have a seal interface to the port.

FIGS. 3A-3C show a carrier 200′, similar to carrier 200, beinginterfaced to tool port 2220 in accordance with an exemplary embodimentwhere the respective seal interfaces (221′ carrier door to carrier, 222′carrier to port, 223′ port door to port and 224′ port door to carrierdoor) form a combined seal 222′ with what may be referred to forconvenience as a general X configuration (seen best in FIG. 3B). In theexemplary embodiment shown, the carrier seal interfaces are shown at thetop opening for example purposes, and in alternate embodiments whereinthe carrier has multiple openings (similar to opening 204 shown in FIG.1, (e.g. top and bottom) sealing interfaces may be provided at eachopening. As may be realized, the general x configuration is merely aschematic representation of the sealing interface surface and inalternate embodiments the sealing interface surfaces may have anysuitable arrangement, for example the seal interface surfaces may becurved. The generally X shaped seal configuration defines multiple sealinterfaces (e.g. 221′-222′) with substantially zero (0) trapped volumebetween the interfaces. Hence, opening of any sealed interface will notresult in a release of contaminants into the space opened on opening ofthe seal interface. Moreover, in other alternate embodiments the sealmay have any desired orientation (e.g. the seal interfaces beingoriented horizontally or vertically in a general + pattern). In theexemplary embodiment, the carrier 200′ is illustrated as a top opening(wall 216′ is door opened by lifting upwards similar to the embodimentillustrated in FIG. 2A) and the port 2220 is configured for bottomloading (lifter lifts carrier 220′ upwards to dock to tool port) forexample purposes. The shell 214′ in this embodiment may have a sealinginterface 214I′ generally beveled sealing faces 221C′, 222C′. Though thesealing faces 222C′, 221C′ on the shell are shown substantially flat, inalternate embodiments the sealing faces may have inclusive or exclusiveangles or other shapes formed therein for enhanced sealing though thesurface is generally pitched to result in the generally X shape sealconfiguration. The wall 216′ of the carrier in this embodiment hassealing interface 216I′ oriented (in the exemplary embodiment shown inFIG. 3A, beveled) generally to define sealing faces 221CD′ and 224CD′.As seen in FIG. 3A, the respective shell and wall sealing faces 221C′,221CD′ are generally complementary defining seal interface 221′ whenwall and shell are closed. The faces 221C′ on the carrier interface 214′form a general wedge providing a guide for the wall 216′ when beingseated onto the shell (see for example FIG. 3C). Also, in the exemplaryembodiment the carrier door to carrier seal interface 221′ may bepositioned so that the weight of the wall 216′ acts to increase sealingpressure on the interface. As may be realized, the cassette andworkpieces supported from the wall 216′ in this embodiment aid insealing the carrier door to carrier. As seen in FIGS. 3A-3B, sealingfaces 222C′ and 224CD′ are disposed to complement the sealing faces222P′, 224PD′ respectively on the port 2220 and port door 2214. FIG. 3Bshows the carrier 200′ docked to the port 2220, and seals 221′, 224′closed. Closure of seals 222′, 224′ seals off and isolates all exposedsurfaces (i.e. surfaces exterior of controlled or isolated chambersinside the carrier or tool) with potential contamination from theinterior/chambers of the tool and carrier. As seen best in FIG. 3B, thegenerally x shape seal 220′ provides for optimal cleanliness as it formswhat may be referred to as a substantially zero lost volume interface.This as noted before means that the seal geometry of seal 220′ does notgenerate substantial pockets or spaces having exterior surfaces that areexposed (i.e. become interior surfaces) when either the carrier door orthe port door is opened. This is best seen in FIG. 3C, wherein removalof the port door 2214, thereby removing the carrier door 216′ does notcause exposure of any previously unsealed/exterior surfaces to thecarrier/process tool interiors.

As seen in FIG. 3C, top opening of the carrier door results, in thisembodiment, in the carrier chamber 202′ being located under the raisedcassette supported from the wall 216′. The carrier chamber 202′ is incommunication with the tool interior, that may have a forced aircirculation system (not shown), which may cause a general venturi flowwithin the carrier chamber. In this embodiment, the circulatory air flowwithin the carrier chamber is located below the workpieces on the raisedcassette (hanging from wall 216′) with minimum potential for depositionof particulates disturbed by the circulation (which settle down awayfrom the workpieces above). In the exemplary embodiment shown in FIGS.3A-3C, the carrier 200′ may be raised, to interface with and dock withthe port 2220 by a suitable lifting device LD. Suitable registrationfeatures LDR may be provided on carrier and lifting device to positionthe carrier on the device and hence position the carrier relative to theport. In alternate embodiments the carrier may be held at the port inany suitable manner. The carrier door 216′ may be locked to the portdoor 2214 via a magnetic lock, mechanical interlocks (e.g. positioned inthe sealed interface between doors) or vacuum suction generated in thesealed interface between doors. The port door 2214 may be opened/closedby a suitable device that may be capable of indexing the cassette(similar to cassette 210 in FIG. 1) past a desired mapping sensor (notshown).

Referring now to FIG. 4, there is shown a carrier 300 in accordance withanother exemplary embodiment, Carrier 300 is generally similar butinverse to carrier 200 with the shell 314 on top of wall 316. Similar tocarrier 200, carrier 300 may be either top (shell operates as door) orbottom (wall operates as door) opening. In the exemplary embodimentshown, the carrier 300 may have integral transport components 300M. Forexample, the carrier shell (or wall) 314, 316 may have transport motivesupports such as rollers or air bearings and a reactive member capableof being motivated by a drive or motor to cause the carrier to be selftransportable (i.e. without using an independent transport vehicle)within the FAB. FIG. 4 illustrates the carrier 300 positioned at aloading port 3010 (generally similar to port 2010 described before) forexample purposes. In the exemplary embodiment shown, the carrier 300 maybe top loaded onto the port interface. The carrier door 316 may bepositioned against or adjacent (to form an interface with) the port door3014, and the shell 314 may interface the port 3012. Carrier 300 andport interface may also have a three, four or five way “cross” type (orzero lost volume) seal similar to the general X seal 220′ shown in FIG.3B. FIG. 4A shows a cross sectional view of the seal 320 in accordancewith one embodiment. In the exemplary embodiment seal 320 may be a fourway seal for a bottom opening configuration but otherwise generallysimilar to seal 220′.

FIG. 4B shows another cross-section of the interface between carrier andport, and the seal therebetween in accordance with another exemplaryembodiment. In this embodiment, seal 320′ is substantially similar toseal 320. FIG. 4B further shows that the shell interface 314I′ may havesupporting flanges/features 326′, 328′. Flange 326′ in this embodimentmay operate wall 316′, for example the flange may overlap a portion ofthe carrier door (though in the embodiment shown the feature defines adoor contact surface, in alternate embodiments, the feature may notcontact the door) and locate a magnetic lock 326M′ to hold the wall 316′to shell 314′ when the carrier door is closed. Further, feature 326′ mayoverlap magnetic lock 3040′ in the port door 3014. The magnetic lock3040′ in the port door may operate for locking the wall 316′ to the portdoor 3014′ for carrier door removal. The position of the carrier shellfeature 326′ may enable the activation of the port door lock 3040′(locking wall 316′ to the port door) and for example cause substantiallysimultaneous unlocking/deactivation of the wall 316′ to shell 314′ lock.Conversely, upon closing of the port door 3014′, unlocking/deactivationof the port door lock 3040′ may cause the magnetic latch 326M′ betweenwall 316′ and shell 314′ to lock. In the exemplary embodiment, exteriorfeature 328′ on the shell may engage a locating/centering feature 3012C′of the port 3010′ to locate the carrier when seated. The shape ofexterior feature 328′ illustrated in FIG. 4B is merely exemplary, and inalternate embodiments the carrier may have any desired locatingfeatures. As noted before, the X configuration of seal 320′ mayeliminate purging the seal interface prior to opening the carrier doorbecause the seal interface may have substantially zero purge volume. Inalternate embodiments, (see for example FIG. 4B), the port may include apurge line 3010A. The purge line 3010A may be on any of the sealinterfaces or between them. FIG. 4C shows another cross section of thecarrier to tool port interface in accordance with another exemplaryembodiment. The carrier to port interface has seal 320″ generallysimilar to seal 320 described before. In this embodiment, the carriershell 314″ may have a support 328″ for seating the carrier 300″ on theport without loading the port door 3014″ (i.e. supporting the carrier3001′ on the port without distributing carrier weight onto the port door3014″) with the carrier door (wall) 316″. Sealing contact at port doorto carrier door seal 321″ remains substantially constant when openingand closing the carrier door.

FIGS. 5A-5C illustrate a carrier 300A, similar to carrier 300, mated toa tool port in accordance with another exemplary embodiment. Carrier300A in this embodiment may be top opening and bottom loaded (in thedirection indicated by arrow +z in FIG. 5A). Carrier shell 316A mayoperate as the carrier door. The seal interface 320A, seen best in FIG.5B is what may be referred to as a three way seal (with substantiallyzero purge or lost volume, similar to seal 320, 220 described before),with a general Y configuration (interface 321A, wall to shell, interface322A wall to port, interface 323A port 3012A to port door 3014A). Inthis embodiment, the port door 3014A may be generally conformal to theshell 316A. For example, shell 316A may be nested in the port door3014A. In the exemplary embodiment, the fit and placement of the shell316A and port door 3014A minimizes the volume at the interface inbetween. A seal (not shown) may be provided between shell 316A and portdoor to seal the interface therebetween. As seen in FIG. 5B, the portdoor, 3014A in this embodiment, may have a vacuum port 3010V to purgethe port door to carrier door interface volume.

Referring again to FIGS. 2A-2B, the carrier to port interface is shownaccording to still other exemplary configurations. Interface 220, 220′is substantially similar in the exemplary embodiments shown in FIGS. 2A,2B (bottom load/top opening, top load/bottom opening respectively). Sealinterface 220, 220′ may be a four way seal with a general “cross” or Xconfiguration (interface 221 wall 216 to shell 214, interface 222 shell214 to port, interface 223 port 2012 to port door 2014 and interface 224port door to wall 216). As seen in FIG. 2A, in this embodiment sealinterfaces 222, 224 may be positioned (e.g. vertically) substantiallyparallel to direction of relative motion of interfacing surfaces (suchas during loading of the carrier, and during closing of the port door).In other words, movement of the carrier or carrier door to closedposition does not generate sealing closure. In this embodiment, one ormore of the faces forming seal interfaces 222, 224, for example, may beprovided with actuable seals such as inflatable seal, piezo actuatedseal or shape memory members to actuate the seal sections and close theseal interface without substantial rubbing contact at the sealinterface. The seal configurations described are merely exemplary.

Referring again to FIG. 1, carrier shell 214 may have external supports240 for handling the carrier. Supports 240 are shown, for example ashandles, but may have any suitable form. In the exemplary embodiment,supports 240 may be located on opposite side of the shell as far apartas desired to optimize handling stability of the carrier. In alternateembodiments more or fewer supports may be provided. Referring now toFIG. 6A, carrier shell 220A may have a perforated or recessed member,membrane or filter 260A located proximate the bottom of the shell. Theperforations or recesses in the member are sized and shaped to mitigateor reduce the strength of venturi or vortex flows induced in the shellwhen the carrier door is open. In alternate embodiments the venturi orvortex flow mitigation elements may be located in any other suitablelocation in the carrier. Carrier 200A is shown with the shell on bottomfor example purposes, and in alternate embodiments the carrier may be ontop. Further flow straightening spaces and/or vanes (not shown) may beprovided within the tool interior to aid maintaining substantiallysmooth/laminar flow over the workpieces when positioned inside the tool.FIG. 6B shows a carrier 200B in accordance with another exemplaryembodiment. The carrier 200B may have a thermal regulator 250 formaintaining the workpieces within the chamber at a different temperaturethen ambient temperature. For example, the carrier shell or wall 214B,216B may have a thermoelectric module connected thermally to theworkpieces, such as via the cassette supports, to heat/raise thetemperature of the workpieces over ambient. Higher workpiece temperaturethan ambient drives particles and water molecules away from theworkpiece via thermophoresis, preventing contamination when workpiecesare out of carrier, or the carrier door is opened. In alternateembodiments, any other desired thermal regulator may be used such asmicrowave energy. In other alternate embodiments, an electrostatic fieldmay be generated around each workpiece to repel contamination by watermolecules and particulates.

Referring now to FIGS. 1A-1B, in the exemplary embodiment the cassette210 (see also FIG. 1) may have nested shelves 210V for 360° positiverestraint of the workpiece supported by the shelf. Each shelf 210V maybe formed by one or more shelf seats or supports 210C. As seen in FIG.1A, in the exemplary embodiment the cassette shelf supports 210C may belocated so that the workpiece is generally straddled by the supports.Each shelf 210V may have a raised surface to form a perimeter constraintfor the workpiece S seated on the shelf. The raised surface may beinclined (relative to the vertical) to form a locating guide 210L forseating the workpiece S. The seating surface of the shelf 210V may bepitched (relative to the bottom surface of the workpiece, forming forexample a pitch angle of about 1° to the workpiece bottom surface) toensure contact with the bottom of the workpiece for example within theperimeter exclusion zone. In alternate embodiments, the workpieceshelves may have any suitable configuration defining passive workpiecerestraints. In other alternate embodiments, the shelves may not havepassive workpiece restraints.

Referring now to FIGS. 7A-7B, the carrier 200C, in accordance withanother exemplary embodiment which is similar to carrier 200 shown inFIG. 1, is shown respectively in closed and opened positions. Cassette210B in this embodiment is capable of variable height. When the carrier200B is closed, cassette 210B may be at a min height, and when thecarrier door (e.g. wall 216B) is opened, the cassette may be expanded toa maximum height. The pitch between workpiece/shelves of the cassette isincreased when cassette expands from min to max height thereby allowingmin carrier height, with maximum space between workpieces when accessed.In this embodiment, the cassette supports 210SB may have a generalbellows configuration. The supports may be made for example of aluminumsheet, or any other suitable material (e.g. shape memory material),allowing sufficient flexibility without articulated joints. As shown,the cassette supports may be supported at the top to the carrier wall216B. Top opening of the carrier (removing wall 216B as shown in FIG.7B) or bottom opening (removing shell 214B similar to that shown in FIG.2B) causes the cassette (bellows) supports 210SB to expand undergravity. The cassette bellows is compressed by closing the carrier door.As seen in FIG. 7C, the bellows 210SB may have workpiece supports 210VBon which the workpieces rest. In the exemplary embodiment, the workpiecesupports 210VB may be shaped, relative to adjoining portions 210PB ofthe bellows, to remain in a substantially constant radial position(hence avoiding relative radial movement between workpiece and workpieceseat) when the bellows expands/collapses. As may be realized, thebellows cassette may be collapsed so that the workpieces in the cassetteare actively clamped between adjacent pleat section 210PB of thebellows. As may be realized, the upper clamping portions may contactworkpiece along its peripheral edge. As seen in FIG. 7B, in theexemplary embodiment a through beam mapper 2060B, or other suitabledevice in the tool or carrier may be provided to determine the locationsof the workpieces S when the cassette is expanded. The workpiece robot(not shown) may also have a sensor for detecting proximity of workpieceto ensure proper positioning for workpiece pick.

As noted before, the carrier with passive carrier door and seal issuitable for direct interface to a vacuum capable chamber such as a loadlock. FIG. 8 shows a carrier 200′ (top opening) to be mated directly toa port interface 4010 of a vacuum capable chamber (referred to forconvenience as load lock) 400 in accordance with another exemplaryembodiment. Carrier 200, shown in FIG. 8 may be generally similar tocarrier 200, 300 described before. The load lock, in the exemplaryembodiment, has an indexer 410 that operates to open/close the port door4014, and hence open/close the carrier door (in this embodiment top wall216′) and raise/lower cassette 210′. In the exemplary embodiment, theindexer 410 may be configured to provide the load lock chamber with alow or minimal Z-height. For example, the indexer 410 may be positionedexterior to the load lock chamber 400C and arranged alongside the loadlock chamber to reduce overall height of chamber and load lock. In theexemplary embodiment, the indexer 410 may have a drive section 412 and acoupling section 414. In the embodiment shown, the drive section 412 mayhave an electromechanical drive system with for example a motor drivingbelt or screw drive to raise/lower shuttle 416. Coupling section 414 inthe exemplary embodiment, may be a magnetic coupling that couples theshuttle 416 on the drive section to the port door 4014. The port doormay for example have magnets (permanent, or electromagnets) or magneticmaterial located thereon forming the interior portion 414I of themagnetic coupling 414. The magnetic portion 414I of the door 4014 mayalso lock the port door to the port frame 4012. For example, the portframe 4012 may have suitable magnets (similar to magnets 2028′ in FIG.2B) arranged to operate with the magnetic portion/magnets 414I on theport door and lock the door and port when the door is in its closedposition. In the exemplary embodiment, the magnetic lock elements in theport frame may operate with the magnetic coupling portion 414I on thedoor 4014. In alternate embodiments the magnetic coupling between doorand drive, and magnetic lock between door and frame may have anysuitable configuration. As seen in FIG. 8, the chamber walls 400Wisolate the drive section 412 from the interior of the chamber 400C. Inother exemplary embodiments (see also FIGS. 18-19), the drive section412′ may be linear motors (e.g. linear induction motors, LIM) thatoperate on a reactive portion 414I′ of the port door 4014′ to effectmovement of the port door. The LIM may be located exterior to thechamber walls and isolated from the chamber interior. In the exemplaryembodiment shown in FIGS. 18-19, the drive may include magnetic materialsections 4122′, or permanent magnets forming fail safe locks to hold theport door 4014′ in the open position in the event of power loss to thechamber. In alternate embodiments, suitable accumulators may beconnected to the drive to allow desired control for lowering the portdoor to the closed position. As may be realized from FIGS. 8 and 18-19,the seal between port door and port frame, in the exemplary embodimentis located so that door weight contributes to sealing the interface.

In the exemplary embodiment shown in FIG. 8, the respective section 414Iof the magnetic coupling may also lock the port door 4014 and carrierdoor 216′ to each other. For example, the carrier door may have suitablemagnets (e.g. permanent magnets) or magnetic material 228′ positioned tocooperate with the coupling section 414I (e.g. may includeelectromagnets, or magnets with variable magnetic field) when activatedto lock port and carrier doors to each other. In the exemplaryembodiment, the port door motion may be guided by a guide that is alsoisolated from the chamber. For example, in the embodiment shown, abellows 400B connects the port door to the chamber walls and isolatesthe port door movement guide 4006 from the chamber. The guide in thisembodiment has generally telescoping sections. The telescoping guide isshown as made from hollow cylindrical telescoping sections for examplepurposes, and may have any suitable configuration in alternateembodiments. In other alternate embodiments, the indexer may have anyother desired configuration. For example, suitable indexing motors maybe located in the chamber walls, but isolated from the chamber interiorsuch as disclosed in U.S. patent application Ser. No. 10/624,987, filedJul. 22, 2003, and incorporated by reference herein in its entirety,capable of effecting controlled movement of the port door withoutmechanical guides for the port door. The bellows 400B may be pressurizedto assist port door closure. The bellows may also house umbilicalsystems such as vacuum line, and power/signal lines connected to theport door. In the exemplary embodiment, the port door may have a portPD10 connected to a vacuum source forming the chamber pump down port aswill be described further below.

Referring now to FIG. 9, there is shown a carrier 300′ on a vacuumchamber 400, in accordance with another exemplary embodiment. In theexemplary embodiment shown, the carrier 300′ may be a bottom openingcarrier (similar for example to carrier 300 described before, see alsoFIG. 3). In the exemplary embodiment, the port door 4014′ may be loweredinto the chamber when opened. The indexer (not shown) may be similar tothat shown in FIGS. 8, 18-19 but arranged to move the port door down.The chamber and port door may have magnetic locks 4028′, 4026′ forlocking the door in the closed position to the chamber frame. In theexemplary embodiment the port frame may have one or more coil elements4028′ (defining the what may be referred to as the frame side portion ofthe magnetic locks. The coil element(s) 4028′ may be positioned asdesired and may generate a magnetic field that operates on door lockcomponents 4026′. The magnetic lock components 4026′ on the door may bepermanent magnets or magnetic material. In the exemplary embodiment, thecoil elements 4028′ are shown located in the chamber for examplepurposes. In alternate embodiments, the coil elements may be locatedoutside. The chamber walls, isolated from the chamber interior. The coilelements may be fixed or stationary relative to the frame. Fieldstrength may be reduced when desired to reduce magnetic forces in themagnetic lock and ease movement of the port door. In alternateembodiments, the coil elements may be movable, for example mounted tothe shuttle of the drive system and may form part of the magneticcoupling between port door and indexer. In alternate embodiments, themagnetic locks may be similar to those for locking the carrier door tothe carrier described before. The permanent magnets or magnetic material4026′ on the port door 4014′ that effect magnetic locking to the frame,may also provide coupling to the indexer similar to that shown in FIG.8. The chamber in the embodiment shown in FIG. 9 may also have a bellowsand port door guide similar to that shown in FIG. 8. The bellows may bepressurized to assist raising the port door and maintain in closedposition, especially when carrier door and cassette are seated on theport door. In alternate embodiments, the chamber may have a bellowswithout a port door guide therein. Vacuum may be connected to the portdoor to effect chamber pump down through the port door to carrier doorinterface. Thus, as in the embodiment shown in FIG. 8, the chamber pumpdown port, in the exemplary embodiment, may be located in the port door.

Referring again to FIG. 8, in the exemplary embodiment load lock chamberpump down may be performed for example with the carrier interfaced tothe chamber port and the port door moved by the indexer 410 from itsclosed position. As may be realized from FIG. 8, in the exemplaryembodiment pump down of the load lock chamber, via vacuum port PD10 inthe port door, may be through the carrier door 216′ to port door 4014interface. The suction flow of chamber/carrier gas through the carrierdoor to port door interface generates a negative pressure on theinterface preventing inadvertent escape of contaminants into thechamber. FIG. 10 illustrates load lock chamber pump down through theport door 5014 in accordance with another exemplary embodiment. In thisembodiment, purge of the port door to carrier door space 5430, and ofthe carrier chamber 202 may be performed prior to load lock chamber pumpdown. For example, purge gas may be introduced into space 5430 byapplying vacuum and cracking a port door to port seal 5223 (or withsuitable valving). The carrier 200 may be purged by cracking the carrierdoor 216 allowing load lock chamber 5400 gas to enter the carrier, oragain by suitable valving. For example, a gas supply from the chamber(shown in phantom in FIG. 10) may be provided to the carrier tointroduce a desired gas species in the carrier 200. As seen in FIG. 10A,which illustrates the load lock chamber 5400 and carrier 200 with theport door and carrier door moved to the open position the load lockchamber 5400 may have a vent (or gas species supply) 5440 disposed asdesired in the load lock walls, to vent the load lock chamber.Accordingly, the purge line may, in the exemplary embodiment, be usedfor purging, and venting of the chamber may be performed independent ofthe carrier door to port door interface.

FIG. 11 illustrates an exemplary embodiment where the carrier door 316Aand port door 6414 have respective mechanical “failsafe” locksrespectively locking the carrier door to carrier 3140 and port door toport 6412 or chamber 6400D. The carrier 314D, carrier door 316D, port6412 and port door 6414 may be passive (no articulated locking parts).In this embodiment, the indexer may be capable of both Z axis indexingof the port door and of rotating the port door (for example about the Zaxis) for engaging/disengaging the lock tabs on the port door andcarrier door. In alternate embodiments, Z axis movement and rotation ofthe port door may be provided via different drive shafts. FIGS. 12A-12Brespectively show bottom views of the carrier shell 314D and the carrierdoor 316D. FIGS. 13A-13B respectively show top plan views of the port6412 in the (load lock) chamber 6400 and the port door 6414. In theexemplary embodiment, the lower surface of the carrier shell hasengagement tabs/surfaces 360D, that are engaged by engagement surfaces362D on the carrier door 316D. As may be realized,engagement/disengagement between engagement surfaces 360D, 362D may beeffected via rotation of carrier door relative to the carrier 314D.Rotation of the carrier door is imparted by the port door 6414 as willbe described below. In alternate embodiments the engagement surfacesbetween door and carrier may have any desired configuration. The carrierdoor 316D may have a male/female torque coupling feature 365Dcomplementing a torque coupling member on the carrier door 6414T. In theexemplary embodiment shown, the port 6412 and port door 6414 may haveinterlocking or engagement surfaces generally similar to the engagementfeatures of the carrier and carrier door. As seen best in FIGS. 13A,13B, the port may have engagement surfaces 6460 (for example projectinginwards), and the port door 6414 may have complementing engagementsurfaces 6462 to overlap and engage port surfaces 6460. As may berealized, in the exemplary embodiment the engagement surface 3600, 3620on the carrier, and the engagement surfaces 6460, 6462 on the port arelocated relative to each other to allow simultaneousengagement/disengagement between carrier and carrier door, and port andport door when the port door is rotated.

FIG. 14 illustrates load lock chamber 400E and indexer 6410E and carrier300E. In the exemplary embodiment the indexer may be locatedsubstantially axially in series with the load lock chamber. Similar topod 200, 300, 3000, pod 300E in the exemplary embodiment shown in FIG. 4may be a vacuum compatible top or bottom opening pod with featuressimilar to those described before. Chamber 6400E may be similar to thechambers described previously. FIG. 15 shows a load lock chamber andcarrier 300F having a reduced pump down volume configuration. In theexemplary embodiment shown, the carrier door 316F may have top 350F andbottom 321F door to carrier shell 314F seals. The bottom seals 3270F(similar for example to seals 221) engage the shell 314F when thecarrier door is closed, as shown in FIG. 15. The top seals 350F sealagainst the carrier shell when the carrier door is opened (for exampleseal 350F may seat and seal against carrier seat surface 351F). The topseal 350F isolates the carrier chamber from the load lock chamber, hencereducing the pump down volume when pumping the load lock chamber tovacuum.

FIGS. 16A-16B show a carrier 300G and load lock chamber 6400Grespectively in docked and undocked positions in accordance with anotherexemplary embodiment. Carrier 300G has a bottom wall 316G, annularsection 314G and a top wall 314PD. In this embodiment the annularsection 314G or one or more portions thereof may operate as a carrierdoor. The top and bottom walls 316G, 314PD may be fixed together and themovable section 314G, defining the door, may have seals 350G, 321G bothtop and bottom for respectively sealing to the top and bottom walls316G, 314PD. Load lock chamber 6400G may have an open port 6402G throughwhich the carrier 300G may be nested into the load lock chamber as seenin FIG. 16B. The load lock chamber 6400G may have a recess 6470G forlowering the carrier door 314G to open access to the carrier. The topwall 314PD of the carrier may seal against the load lock chamber portthereby sealing the load lock chamber and allowing pump down of thechamber. A suitable elevator may be provided to raise/lower the carrierdoor 314G. FIGS. 17-17C, show another top sealing carrier 300H and loadlock chamber 6400H in accordance with another exemplary embodiment. Thecarrier 300H may have a top sealing flange 314H and side opening 304H(along a carrier edge for loading/unloading of workpieces). In theexemplary embodiment, the carrier top sealing flange 314H seats andseals against the rim 6412H of the chamber port as shown best in FIG.17B. The carrier door 314DR may be opened by radial outward androtational motion indicated by arrow 0 in FIG. 17C. The carrier openingis aligned with a slot valve in the load lock chamber. Although theexemplary embodiments have been described with specific reference to aload lock chamber, the features described are equally applicable to aload port chamber such as shown in FIG. 18. The interior of the loadport chamber may have a controlled atmosphere, but may not beisolatable.

Referring to FIGS. 29A and 29B, there is shown a schematic plan view ofan automated material handling system 10, 10′ in accordance with anotherexemplary embodiment. The automated material handling system 10, 10′shown for example, in FIGS. 29A and 29B generally includes one or moreintrabay transport system section(s) 15, one or more interbay transportsystem section(s) 20, bay queue sections 35, transport sidings or shuntsections 25 and workpiece carriers or transports. The terms intrabay andinterbay are used for convenience and do not limit the arrangement ofthe transport system 10110′ (as used herein inter generally refers to asection extending across a number of groups, and intra refers generallyto a section extending for example within a group). The transport systemsections 15, 20, 25, 35 may be nested together (i.e. one transport loopwithin another transport loop) and are generally arranged to allow thehigh-speed transfer of semiconductor workpieces, such as for example,200 mm wafer, 300 mm wafers, flat display panels and similar such items,and/or their carriers to and from, for example, processing bays 45 andassociated processing tools 30 in the processing facility. In alternateembodiments, any suitable material may be conveyed in the automatedmaterial handling system. The transport system 10 may also allow for theredirection of workpieces from one transport section to any anothertransport section. An example of an automated material handling systemfor transporting workpieces having interbay and intrabay branches can befound in U.S. patent application entitled “Automated Material HandlingSystem” having Ser. No. 10/697,528 previously incorporated herein byreference in its entirety.

The configurations of the automated material handling system 10, 10′shown in FIGS. 29A and 29B are representative configurations, and theautomated material handling system 10, 10′ may be disposed in anysuitable configuration to accommodate any desired layout of processingbays and/or processing tools in a processing facility. As can be seen inFIG. 29A, in the exemplary embodiment the interbay transport sections 15may be located on one or more side(s) of and connected to each other byany number of transport sections 20, corresponding for example to one ormore processing bay(s) 45. In alternate embodiments the outer or sidetransport sections may be intrabay sections, and the sections traversingin between may be linking the intrabay sections to groups or arrays ofprocessing tools within a bay. The interbay transport sections 15 ofFIG. 29A, in the exemplary embodiment, may also be connected by across-shunt 50 that allows the movement of a workpiece transportdirectly between interbay transport sections 15 without passing througha processing or fab bay 45. In yet other alternate embodiments, thetransport sections 15 may be connected to each other by additionalintrabay transport sections (not shown). In other exemplaryembodiment(s), such as shown in FIG. 29B, the interbay transport section15 may be located between any number of processing bays 45, henceforming for example a generally center isle or a transport centralartery between the branch sections serving bays or tool groups 45. Inother alternate embodiments, the intrabay transport section may form aperimeter around and enclose any number of processing bays 45. In yetother alternate embodiments, there may be any number of nested loopsections such as for example N number of systems, such as system 10 or10′ as shown in FIGS. 29A and 29B, connected generally in parallel bytransport sections that directly connect each of the interbay transportsections 15. In still other alternate embodiments, the transportsections 15, and processing tools may have any suitable configuration.In addition, any number of intrabay/interbay systems may be joinedtogether in any suitable configuration to form nested processing arrays.

The interbay transport section 15, for example may be a modular tracksystem that provides for the movement of any suitable workpiecetransport. Each module of the track system may be provided with asuitable mating means (e.g. interlocking facets, mechanical fasteners)allowing the modules to be joined together end to end duringinstallation of the intrabay transport sections 15. The rail modules maybe provided in any suitable length, such a few feet, or in any suitableshape, such as straight or curved, for ease of handling duringinstallation and configuration flexibility. The track system may supportthe workpiece transport from beneath or in alternate embodiments, thetrack system may be a suspended track system. The track system may haveroller bearings or any other suitable bearing surface so that theworkpiece transports can move along the tracks without substantialresistance over the rollers. The roller bearing may be tapered or thetacks may be angled towards the inside of a curve or corner in the trackto provide additional directional stability when the workpiece containeris moving along the track.

The intrabay transport sections 15 may be a conveyor based transportsystem, a cable and pulley or chain and sprocket based transport system,a wheel driven system or a magnetic induction based transport system.The motor used to drive the transport system may be any suitable linearmotor with an unlimited travel capable of moving workpiece containersalong the intrabay transport sections 15. The linear motor may be asolid state motor without moving parts. For example, the linear motormay be a brushed or brushless AC or DC motor, a linear induction motor,or a linear stepper motor. The linear motor may be incorporated into theintrabay transport sections 15 or into workpiece transports orcontainers themselves. In alternate embodiments, any suitable drivemeans may be incorporated to drive the workpiece transports through theintrabay transport system. In yet other alternate embodiments, theintrabay transport system may be a pathway for trackless wheeledautonomous transport vehicles.

As will be described below, the intrabay transport sections 15 generallyallow for uninterrupted high-speed movement or flow of the workpiecetransports along the path of the intrabay transport sections 15 throughthe use of queue sections and shunts. This is highly advantageouscompared to conventional transport systems that have to stop the flow ofmaterial when a transport container is added or removed from a transportline.

As noted before, in the exemplary embodiment, the intrabay transportsections 20 may define processing or fab bays 45 and may be connected tothe interbay transport section(s) 15 through queue sections 35. Thequeue sections 35 may be located for example on either side of theinterbay or intrabay transport sections 15, and allow a workpiece orworkpiece container to enter/exit the intrabay transport sections 20without stopping or slowing down the flow of material along either theinterbay transport sections 15 or the flow of material along theintrabay transport sections 20. In the exemplary embodiment, the queuesection 35 are schematically shown as discrete sections from transportsections 15, 20. In alternate embodiments the queue section, or thequeue paths between transport sections 15, 20 may be formed integral tothe transport sections but defining discrete queue transport pathsbetween transport sections. In alternate embodiments the queues may bepositioned on the interbay and intrabay sections as desired. An exampleof a transportation system having a travel lane and an access or queuelane, allowing selectable access on and off the travel lane withoutimpairment of the travel lane, is described in U.S. patent applicationentitled “Transportation System” with Ser. No. 11/211,236 previouslyincorporated herein by reference in its entirety. The intrabay transportsections 20 and the queue sections 35 may have track systems that aresubstantially similar to that described above for the interbay transportsections 15. In alternate embodiments, the intrabay transport sectionsand the queue sections tying intra and inter transport sections may haveany suitable configuration, shape or form and may be driven in anysuitable manner. As can best be seen in FIG. 29A, in the exemplaryembodiment the queue sections 35 may have an input section 35A and anoutput section 35B that correspond to the direction of movement R1, R2of the intrabay and interbay transport sections 20, 15. The conventionused herein for example purposes defines section 35A as input to section20 (exit from section 15) and section 35B as exit/output from section 20(input to section 15). In alternate embodiments the travel direction ofthe queue sections may be established as desired. As will be describedbelow in greater detail, workpiece containers may exit the interbaytransport sections 15 via the input section 35A and enter the interbaytransport sections 15 via the output section 35B. The queue sections 35may be of any suitable length to allow for the exiting or entering ofthe workpiece transports on and off the transport sections 15, 20.

The intrabay transport sections 20 may extend within corridors orpassages connecting any number of process tools 30 to the transportsystem 10, 10′. The intrabay transport sections 20 may also connect twoor more interbay transport sections 15 to each other as shown in FIG.29A and as described above. The intrabay transport sections 20 are shownin FIGS. 29A and 29B as having an closed loop shape however, inalternate embodiments they may have any suitable configuration or shapeand may be adaptable to any fabrication facility layout. In theexemplary embodiment, the intrabay transport sections 20 may beconnected to the process tool(s) 30 through a transport siding or shunt25, which may be similar to the queue section 35. In alternateembodiments, shunts may be provided on the interbay transport sectionsin a similar manner. The shunts 25 effectively take the workpiecetransports “off line” and have for example input sections 25A and outputsections 25B corresponding to the direction of travel R2 of the interbaytransport sections 20 as can be seen in FIG. 29A. The shunts 25 allowthe workpiece transports to exit and enter the intrabay transportsections 20, through the input and output sections 25A, 25B,substantially without interrupting the substantially constant velocityflow of workpiece transports on the intrabay transport sections 20.While in the shunt 25, the workpiece container may, for example, stop ata tool interface station that corresponds to the location of the processtool station 30, so that the workpieces and/or the container itself maybe transferred into the process tool load port or any other suitableworkpiece staging area by or through any suitable transfer means, suchas for example, an equipment front end module, sorter or any othersuitable transfer robot. In alternate embodiments, workpiece transportsmay be directed to desired shunts to effect reorder (e.g. reshuffling)of the transports on the given transport section.

The switching of the workpiece carriers or transports from and betweenthe different sections 15, 20, 25, 35 may be controlled by a guidancesystem (not shown) connected to a controller (not shown). The guidancesystem may include positioning devices allowing for positiondetermination of the transports moving along the sections 15, 20, 25,35. The positioning devices may be of any suitable type such ascontinuous or distributed devices, such as optical, magnetic, bar codeor fiducial strips, that extend along and across the sections 15, 20,25, 35. The distributed devices may be read or otherwise interrogated bya suitable reading device located on the transport to allow thecontroller to establish the position of the transport on the section 15,20, 25, 35 as well as the kinematic state of the transport.Alternatively, the devices may sense and/or interrogate a sensory item,such as a RFID (rapid frequency identification device), on thetransport, workpiece carrier or workpiece, to identifyposition/kinematics. The positioning devices may also include, alone orin combination with the distributed devices, discrete positioningdevices (e.g. laser ranging device, ultrasonic ranging device, orinternal positioning system akin to internal GPS, or internal reverseGPS) able to sense the position of the moving transport. The controllermay combine information from the guidance system with the position feedback information from the transport to establish and maintain thetransport paths of the transport along and between the sections 15, 20,25, 35.

In alternate embodiments, guidance system may include or have grooves,rails, tracks or any other suitable structure forming structural ormechanical guide surface to cooperate with mechanical guidance featureson the workpiece transports. In still other alternate embodiments, thesections 15, 20, 25, 35 may also include electrical lines, such as aprinted strip or conductor providing electronic guidance for theworkpiece transports (e.g. electrical lines sending a suitableelectromagnetic signal that is detected by a suitable guidance system onthe transports).

Still referring to FIGS. 29A and 29B, an exemplary operation of thetransport system 10, 10′ will now be described. A workpiece container,located for example in a shunt 25 may enter the transport system 10,10′. To maintain the flow of the intrabay transport section 20substantially uninterrupted and moving at a generally constant velocity,the workpiece container may access the interbay transport section 20 viashunt 25. The workpiece transport accelerates within the shunt 25 sothat the transport is traveling the same speed as the flow of materialin the intrabay transport section 20. The shunt 25 allows the workpiecetransport to accelerate, and hence the transport may merge into the flowof the intrabay transport section 20 without hindering that flow orcolliding with any other transports traveling in the interbay transportsection 20. In merging with the intrabay transport section 20, theworkpiece transport may wait in the shunt 25 for suitable headway sothat it may enter the flow of the intrabay transport section freely,without colliding with any other workpiece carriers or transports orcausing reduction in velocity of transports traversing the intrabaysection. The workpiece transport continues, for example, along theintrabay transport section 20 at a substantially constant speed andswitches, with the right-of-way, onto the output queue area or section35B for example to switch an interbay section 15. In one embodiment, ifthere is no room within the output queue section 35B, the transport maycontinue to travel around the intrabay transport section 20 until theoutput queue section 35B becomes available. In alternate embodiments,cross shunts may be provided connecting opposing travel paths of thetransport section, allowing transports to switch between transport pathsto, for example, return to a bypassed station without traveling thewhole loop of the transport section. The transport may wait in the bayoutput queue section 35B for suitable headway, then accelerate and mergeinto the generally continuous constant velocity flow of the interbaytransport section 15 in a manner substantially similar to the mergedescribed above for the intrabay transport section 20. The transport mayfor example continue at a generally continuous speed along the interbaytransport section 15 to a predetermined bay and is switched onto theassociated queue input section 35A for entry to desired intrabay section20. In one embodiment, if there is no room within the input queuesection 35A, the transport may continue to travel around the intrabaytransport section 15 until the input queue section 35A becomes availablein a manner similar to that described previously. The transport may waitin the input queue section 35A for suitable headway and accelerate tomerge onto a second intrabay transport section 20, the second intrabaytransport section 20 again having a continuous constant velocity flow.The transport is switched off of the second intrabay transport section20 and onto the transport shunt 25 where the transport interfaces withthe process tool 30. If there is no room in the shunt 25 for thetransport, due to other transports in the shunt 25, the transportcontinues to travel along the intrabay transport section 20, with theright-of-way, until the shunt 25 becomes available. Because the flow ofmaterial in the interbay transport sections 15 and the intrabaytransport sections 20 is substantially uninterrupted and travels at agenerally constant velocity, the system can maintain a high throughputof workpiece transports between processing bays and processing tools.

In the exemplary embodiment shown in FIG. 29A, the transport may traveldirectly between processing bays via an extension 40 that may directlyconnect the queue sections 35, processing tools, intrabay transportsections 20 or interbay transport sections 15 together. For example, asshown in FIGS. 29A and 29B, extensions 40 connect the queue sections 35together. In alternate embodiments, the extensions 40 may provide accessfrom one processing tool to another processing tool by connecting thetransport shunts, similar to shunts 25, of each of the tools together.In yet other alternate embodiments, the extensions may directly connectany number or any combination of elements of the automated materialhandling system together to provide a short access route. In largernested networks, the shorter path between destinations of the transportcreated by the extensions 40 may cut down traveling time of thetransports and further increase productivity of the system.

In still other alternate embodiments the flow of the automated materialhandling system 10, 10′ may be bi-directional. The transport sections15, 20, 25, 35, 40, 50 may have side by side parallel lanes of traveleach moving in opposite directions with exit ramps and on ramps loopingaround and connecting the opposite lanes of travel. Each of the parallellanes of the transport sections may be dedicated to a given direction oftravel and may be switched individually or simultaneously so that thetravel for each of the respective parallel lanes is reversed accordingto a transport algorithm to suit transport loading conditions. Forexample, the flow of material or transports along the parallel lanes ofa transport section 15, 20, 25, 35, 40, 50 may be flowing in itsrespective direction. However, if at a later time it is anticipated thatsome number of workpiece transports are situated in the facility and aregoing to a location where it would be more efficient to move along oneof those parallel lanes in a direction opposite the current flowdirection, then the travel directions of the parallel lanes may bereversed.

In alternate embodiments, the bi-directional lanes of travel may belocated in stacks (i.e. one above the other). The interface between theprocess tool and the transport shunts 25 may have an elevator typeconfiguration to raise or lower a transport from a shunt to the processtool load port, for example, such as where a shunt having a clockwiseflow of material is located above a shunt with a counterclockwise flowof material. In alternate embodiments, the bi-directional shunts andother transport sections may have any suitable configuration.

FIG. 20 shows a portion of a transport system track 500 of a transportsystem, for transporting carriers between tool stations in accordancewith another exemplary embodiment. The track may have a solid stateconveyor system, similar to that described in U.S. patent applicationSer. No. 10/697,528 previously incorporated by reference. The track mayhave stationary forcer segments cooperating with reactive portionintegral to the carrier shell/casing. The carrier may thus betransported directly by the conveyor. The transport system 500 shown inan asynchronous transport system in which transport of carriers issubstantially decoupled from the actions of other carriers on thetransport system. The track system is configured to eliminatedetermining factors affecting transport rate of a given carrier due toactions of other carriers. Conveyor track 500 employs main transportpaths with on/off branching paths (see also FIGS. 297-298) that routes acarrier away from the main transport path to effect routing changesand/or interface with tool stations (buffer, stocker, etc.) withoutimpairing transport on main transport path. Suitable example oftransport system with branching on/off paths is disclosed in U.S. patentapplication Ser. No. 11/211,236 previously incorporated by reference. Inthis embodiment segments 500A, C, D may have winding sets for A1-Dlinear motor causing movement along the main travel path 500M (this isshown in FIG. 20A). Segment 500B is illustrated for example in FIG. 20as an off/exit to what may be referred to as access path 500S. Thewindings of the forcer in this segment be arranged to provide in effecta 2-D planar motor to allow both motion along main path 500M and whendesired effect movement of the carrier(s) along path 500S (see FIG.20B). The motor controller may be a zoned controller similar to thedistributed control architecture described in U.S. patent applicationSer. No. 11/178,615, filed Jul. 11, 2005 incorporated by referenceherein in its entirety. In this embodiment, the drives/motors may bezoned, efficiently controlled by zone controllers with appropriate handoff between zones. The conveyor 500 may have suitable bearings tomovably support carrier. For example, in segments 500A, 500C and 500D,bearings (e.g. roller, ball may allow 1 degree of freedom movement ofthe carrier along path 500M).

Bearings in segment 500B may allow 2-degree of freedom movement of thecarrier. In other embodiments, bearings may be provided on the carrier.In still other embodiments air bearings may be used to movably supportthe carrier on the track. Guidance of the carriers between path 500M anddirection onto path 500S may be effected by suitable guide system suchas steerable or articulated wheels on the carrier, articulated guiderails on the track, or magnetic steerage as shown in FIG. 20B.

FIG. 20A illustrates an exemplary transport element 500A of system 500.The exemplary embodiment shown illustrates a segment with single travellane or path (e.g. path 500M). As seen in FIG. 20A, in the exemplaryembodiment the segment has linear motor portion or forcer 502A andsupport surface(s) 504(A) for motive supports on the transport. As notedbefore, in alternate embodiments the transport segment may have anyother desired configuration. In the exemplary embodiment, guide rails506A may be used to guide the transport. In alternate embodiments, thetransport segment may have magnets or magnetic bearings in lieu of railsfor transport guidance. An electromagnet on the carrier may be used toassist decoupling the carrier from the track. FIG. 20B illustratedanother transport segment of the transport system 500 in accordance withanother exemplary embodiment. Segment 500A′ may have multiple travellanes (for example intersecting lanes similar to segment 500B shown inFIG. 20) or substantially parallel main travel lanes (similar to paths500M) with switching therebetween. As seen in FIG. 20B, in the exemplaryembodiment, the travel lanes (similar to paths 500M, 500S) are generallydefined by the 1-D motor sections 502A1 and corresponding carrier motivesupport surfaces/areas 504A′. The intersection or switch between thetravel lanes is formed by an array of 2-D motor elements capable ofgenerating desired 2-D forces on the transport to effect traversebetween travel lanes 500M′, 500S′.

FIG. 21 shows an intersection, or turn segment of the conveyor transportsystem in accordance with another exemplary embodiment. In the exemplaryembodiment shown, the transport segment 500A″ defines multiple travellanes 50M″, 500S″ that intersect. The travel lanes are generally similarto lane 500M (see FIG. 20A). In the exemplary embodiment, the transportvehicle may traverse a given lane 500S″, 500M″ until generally alignedwith the intersecting lane. When aligned, the 1-D motor of the desiredlane commences to move the transport along the intersecting lane. Inalternate embodiments, the intersection may not be oriented at 90°. FIG.20C shows the bottom of the carrier 1200 and the reactive elementstherein. As may be realized the reactive elements may be arranged tocoincide with the orientation of the respective forcer sections at theintersection (see for example FIG. 21). This allows the carrier tochange tracks at the intersection substantially without stoppage. FIG.20D shows the reactive elements 1202FA positioned on a pivotal sectionof a carrier 1200A that may be rotated to desired position in accordancewith another exemplary embodiment. FIG. 22 shows a track segment 500H′″with a beside track storage location 500S′″, generally similar to theintersection shown in FIG. 21. FIGS. 23-23A show track segments 500,with cutouts or openings 1500O for lift arms of a carrier lift orshuttle, (not shown) as described further below. In the exemplaryembodiment, the openings 1500O allow side access to the carrier for abottom pick of the carrier from the conveyor track. FIG. 24 shows atrack segment 2500A with the forcer (such as a linear motor) 2502Alocated offset from carrier/track centerline indicated by arrow 2500M.

FIGS. 25A-25B show a linear motor conveyor 3500 (having grounded forcersegments and reaction elements embedded within the carrier 3200) fortransporting substrates within a semiconductor FAB. In the exemplaryembodiment shown, the conveyor 3500 may be inverted (e.g. carrier issuspended from and is located below conveyor), as shown such that thecarrier is accessible from directly below. The conveyor 3500 mayotherwise be similar to transport system segments 500A, 500A″, 500A′″described previously. In the exemplary embodiment, a magnetic retentionforcer 3502 may be employed to maintain the coupling between theconveyor 3500 and carrier 3200. This force may arise from the linearmotor coils (e.g. in a linear synchronous design) and/or via separateelectromagnets and/or permanent magnets (not shown) providedspecifically for that purpose. Coupling and decoupling of the carrier tothe conveyor is rapid and may be achieved without moving parts (e.g., anelectromagnetic switch). Failsafe operation may be assured via flux pathand/or passive mechanical retention features between carrier andconveyor.

In the exemplary embodiment intersections and branch points (i.e.,merge-diverge locations similar for example to segment 500B in FIG. 20)may be achieved with coil switching. In alternate embodiments,turntables or other routing devices, may be used to transfer carriersbetween travel paths of the conveyor 3200.

In the exemplary embodiment the carrier 3200 may be arranged such thatthe reaction elements are on the top, and the substrates are accessedfrom the bottom of the carrier. In the exemplary embodiment, carrier3200 may have a magnetic platen located to cooperate with the forcer ofconveyor 3500. The carrier platen =, or platen section may includerollers, bearing or other motive support surfaces (e.g. reaction surfacefor air bearings in the conveyor). The platen may also include anelectromagnetic coupling allowing the container portion of the carrierto decouple from the platen portion that may remain connected to theconveyor when the workpiece container portion is loaded on a processingtool 3030.

In the exemplary embodiment, to load a tool, the conveyor 3200 positionsa carrier at the tool loadport, and for example a dedicated verticaltransfer mechanism 3040 may be used (see also FIGS. 26A-26B) to lowerthe carrier from the conveyor elevation to the (controlled environment)loading interface 3032 of the tool 3030. The vertical transfer devicemay also be used as an indexer, thereby positioning the wafers foraccess by a wafer-handling robot. A suitable example of a verticaltransfer device is described in U.S. patent application Ser. No.11/210,918, filed Aug. 25, 2005 and previously incorporated by referenceherein.

In alternate embodiments, the conveyor may be a powered-wheelaccumulating conveyor positioned in an inverted arrangement and having asuitable magnetic attractive force to hold the carrier on the conveyorwheels. In other alternate embodiments, the general arrangement may beinverted such that the conveyor is below the loadport, the carrier hasreaction features on the top.

FIGS. 26A-26B show other examples of direct lower/lift carriers fromtransport system to load port/tool interface. In the exemplaryembodiments shown in FIGS. 26A-26B, the carriers may have a reactionplaten that may be integral to the carrier. In other embodiments theplaten, as noted before, may be detachable from the carrier, for exampleremaining on/coupled to the conveyor when the carrier is removed. Insuch a case, each platen in the transport system corresponds in asubstantially 1:1 relationship to the carriers in the FAB.

FIG. 27 illustrates a carrier 4200 having a conveyor vehicle hybridconfiguration in accordance with another exemplary embodiment. Carriervehicle(s) 4200 may be provided for automated conveyance of payloads(such as carriers containing semiconductor substrates). The vehicles maycarry stored energy for self-propulsion, a steering system, at least onemotor-powered drive wheel, sensors for odometry and obstacle detection,and associated control electronics. In addition the vehicles areoutfitted with one or more reaction elements (similar to magneticplatens described before) that can cooperate with stationary linearmotor forcer segments of a conveyor 4500, similar to conveyor system 500(see also FIG. 20).

In the exemplary embodiment, when a vehicle(s) 4200 is traveling alongthe path (similar to paths 500M, 500J) defined by one or more forcersegments, the drive motor may be disconnected from the drive wheel(s),and the vehicle be passively urged along the path via electromagneticcoupling with the reaction elements in the conveyor 4500. If the storedenergy device (e.g. batteries, ultracapacitors, flywheel, etc.) withinthe vehicle needs to recharge, the motion of the traction wheel(s) alongthe guideway may be used to convert energy from the linear motor to thevehicle storage. In the case of electrical energy storage, this may beaccomplished by re-connecting the vehicle drive motor to be used as agenerator with suitable monitoring and conditioning electronics. Such“on-the-fly” charging has the benefit of simplicity and ruggedness, andsuch an arrangement affords significant flexibility and fault tolerance.For example, vehicle(s) 4200 may be capable of driving autonomously pastfailed conveyor segments, around obstacles or between work areas notserviced by a conveyor (see FIGS. 27A, 27B). The number and length ofconveyor forcer segments may be tailored to an operating scheme such asa conveyor for interbay transport, and using autonomous vehicle motionwith the bay for example. Self-directed steering may be used forflexible route selection. Self-directed cornering could be used toeliminate curved forcer segments. High-speed travel may be effectedalong conveyor runs and, if desired, separated from operators by safetybarriers. Conveyor sections may be used for long runs, such as links toadjacent FABs. Conveyors may be used for grade changes, mitigating thedifficulties encountered by vehicles using exclusively stored energy.

FIG. 28 shows another example of an integrated carrier and transportvehicle. In contrast to conventional vehicle-based semiconductorautomation, in which vehicles are dispatched to transport workpiececarriers, within a FAB, in the exemplary embodiment each carrier 5200 isa vehicle. The integrated carrier/vehicle 5200 in the exemplaryembodiment may be similar to vehicle 4200 described before. In alternateembodiments, the carrier vehicle may have any desired vehicle features.In the exemplary embodiment vehicle 5200 may include integral carrier5202 and vehicle 5204 portions. The carrier 5202 is shown as front/sideopening in FIG. 28 for example purposes. In alternate embodiments, thecarrier may be top opening or may have any other suitable workpiecetransfer opening. The vehicle may drive directly to the loadport wherework pieces are to be transferred, or may be engaged by anotherautomation component such as a tool buffer. Substantially permanentlyfixing the carrier 5202 and vehicle 5204 eliminates the time waiting fora free vehicle to be dispatched when a lot transfer is desired, as wellas the associated deliver time variance. Further, the carrier vehicle5200 eliminates “empty-car” moves and hence may reduce the total trafficon the transport network improving the system capacity. In alternateembodiments, the carrier and vehicle may have a coupling for detachingcarrier from vehicle. Though vehicles in the system may be apportionedto carriers in a 1:1 relationship to eliminate delays in carriertransport awaiting for vehicles, system knowledge in a suitablecontroller may be used to allow separation in limited instances (e.g.repair/maintenance or either vehicle or workpiece carrier sections).Otherwise, the carrier and vehicle remain an integral unit duringtransport or when engaged to a tool loading station or other automationcomponent of the FAB.

FIG. 29C shows a plan view of a horizontally arrayed buffering system6000 that may interface between a conveyor system 500 (or any otherdesired carrier transport system) and tool stations 1000 in accordancewith another exemplary embodiment. The buffering system may be locatedunder tool stations or portions thereof or above the tool stations. Thebuffering system may be positioned away (i.e. below or above) fromoperator access ways. FIG. 30 is an elevation view of the bufferingsystem. FIGS. 29C-30 show the buffering system located on one side ofconveyor 500 for example purposes. The buffering system may be extendedto cover as large a portion of the FAB floor as desired. In theexemplary embodiment shown, operator walkways may be elevated above thebuffering system. Similarly, the buffering system may be extendedanywhere in the FAB overhead. As seen in FIGS. 29C-30, in the exemplaryembodiment the buffering system 6000 may include a shuttle system 6100(which may have suitable carrier lift or indexer) capable of at least3-D movement and an array of buffer stations ST. The shuttle system maygenerally include guide system (e.g. rails) 6102 for one or moreshuttle(s) 6104 capable of at least 2-D traverse over the guide system.The arrangement of the shuttle system illustrated in FIGS. 29C-30 ismerely exemplary and in alternate embodiments the shuttle system mayhave any other desired arrangement. In the exemplary embodiment, theshuttle system shuttles or interfaces between the conveyor 500, bufferstations ST and tool loading stations LP (see FIG. 29C). The shuttle(s)6102 are capable of traversing between horizontally disposed conveyor500 (for example via an access lane 602 between the segments 600 of theconveyor) and buffer storage ST or loading locations LP on the toolstations to shuttle carriers 200 therebetween. As seen best in FIG. 30,in the exemplary embodiment, the shuttle(s) 6104 may include an indexer6106 for picking/placing the carrier on the conveyor 600, or bufferstations ST or tool loadport LP. The buffering system may be configuredin modular form allow the system to be easily expanded or reduced. Forexample, each module may have corresponding storage location(s) ST andshuttle rails and coupling joints for joining to other installed modulesof the buffering system. In alternate embodiments, the system may havebuffering station modules (with one or more integral buffering stations)and shuttle rail modules allowing modular installation of the shuttlerails. As seen in FIG. 29C, the access lane(s) 60L of the conveyor 500may have shuttle access ways allowing the shuttle indexer to access thecarrier through the conveyor lane. FIG. 31 shows elevation of abuffering system 6000 communicating with the merge/diverse lane of theconveyor 500. In the exemplary embodiment, the buffering system shuttle6104 may access carriers directed onto the access lane of the conveyors.Stops (or lack of accessways similar to lanes 602 in FIG. 29C) may limitthe shuttle from accessing or interfering with the travel lane of theconveyor. FIG. 32 is yet another elevation showing multiple rows ofbuffering stations. The buffering system may have any desired number ofbuffering stations in any desired number of rows. Shuttle traverse (inthe direction indicated by arrow Y in FIG. 32) may be adjusted asdesired by modular replacement of traverse guide 61087. In otheralternate embodiments, the buffering stations may be arrayed in multiplehorizontal planes or levels (i.e. two or more levels that may bevertically separated (to allow carrier height pass through betweenlevers). Multilevel buffering may be used with reduced capacitycarriers. FIG. 33 shows another plan view of a buffering system with aninterface to a guided vehicle carrier V. FIG. 34 shows an elevation viewof an overhead buffering system 7000 otherwise similar to the under toolbuffering system 6000 described before. The overhead buffering system7000 may be used in conjunction with the under tool buffering system(similar to system 6000). The overhead buffering system is showninterfacing with an overhead conveyor 500. In alternate embodiments, theoverhead system may interface with a floor conveyor system or floorbased vehicles. Suitable control interlocks (e.g. hard) may be providedto prevent horizontal traverse of shuttle with lowered payload that mayimpinge walkway vertical clearances. Top shields over the walkway may beused for preventing suspended loads from crossing through walkway space.

FIG. 35 shows a looped buffering system 8000. The buffering stations STof the system may be movable, mounted on a track 8100 (in the exemplaryembodiment shown as being closed looped) that moves the buffer stationsST between loading position(s) R in which carriers may be loaded intothe buffer stations ST (for example with overhead loading) and loadingstation(s) LP of a tool interface. The tool interface may have anindexer for loading the carrier to the tool station.

It should be understood that the foregoing description is onlyillustrative of the invention. Various alternatives and modificationscan be devised by those skilled in the art without departing from theinvention. Accordingly, the present invention is intended to embrace allsuch alternatives, modifications and variances which fall within thescope of the appended claims.

1. An semiconductor workpiece processing system comprising: at least oneprocessing tool for processing semiconductor workpieces; a primarytransport system having one or more constant velocity transport loops; asecondary transport system having one or more constant velocitytransport loops, the secondary transport system being connected to theprimary transport system through queue sections wherein, the queuesections are configured to allow the movement of material between theprimary transport system and secondary transport system withoutdisrupting the flow of either the primary or secondary transportsystems; and one or more interfaces connected to the one or moretransport loops of the secondary transport system through interfaceshunts for interfacing with the at least one processing tool, whereinthe interface shunts are configured to allow the movement of materialbetween the one or more transport loops of the secondary transportsystem and the one or more interfaces without disrupting a flow of thesecondary transport system; wherein the flow of material along theprimary and secondary transport systems is continuous.
 2. The automatedmaterial handling system of claim 1 wherein the one or more constantvelocity transport loops of the primary transport system are connectedto each other through the one or more constant velocity transport loopsof the secondary transport system.
 3. The automated material handlingsystem of claim 1 wherein the one or more constant velocity loops of thefirst transport system are connected to each other through one or morecross shunts.
 4. The automated material handling system of claim 1wherein the one or more constant velocity loops of the second transportsystem are connected to each other through one or more cross shunts. 5.The automated material handling system of claim 1 wherein at least oneof the one or more constant velocity loops of the first transport systemare connected to another of the one or more constant velocity loops ofthe first transport system through queue sections.
 6. The automatedmaterial handling system of claim 1 wherein the automated materialhandling system if configured for the transportation of containers forholding at least one semiconductor workpiece therein for transport toand from the processing tool.
 7. The automated material handling systemof claim 1 wherein the primary and secondary transport systems areconfigured to allow a workpiece container designated to be transferredto a queue section or an interface shunt to continue traveling along theprimary or secondary system until the queue section or interface shuntbecomes available.
 8. The automated material handling system of claim 1wherein the primary transport system, the secondary transport system,the queue sections and the interface shunts each comprise a set ofparallel tracks wherein each track of the set of parallel tracks isconfigured to provide transportation of workpiece carriers in oppositedirections from each other.